Windows Authentication for ASP.NET MVC 4 – how it works, how to test it

I have never used Windows Authentication for ASP.NET MVC web applications before, but Forms Authentication. Recently, I have had an ASP.NET MVC 4 web application that requires a Windows Authentication implementation for users who are granted to log in my company web server. So, I have some questions regarding Windows Authentication. I am using Visual Studio 2012.

Mailbox unavailable. The server response was: 5.7.1 Unable to relay for [email protected]

I am getting “Mailbox unavailable. The server response was: 5.7.1 Unable to relay for [email protected]” when I try to send the mail using ASP.NET. The site is deployed on IIS7, Windows 2008 server. The website was working fine on IIS6 and Windows 2003 Server. I deployed it on IIS7, 2008 it has started giving me … Read more